Noisy propagation of Gaussian states in optical media with finite bandwidth

Berihu Teklu; Matteo Bina; Matteo G. A. Paris

doi:10.1038/s41598-022-15865-5

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arXiv · 2205.07837

Noisy propagation of Gaussian states in optical media with finite bandwidth

Berihu Teklu·Matteo Bina·Matteo G. A. Paris

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Abstract

We address propagation and entanglement of Gaussian states in optical media characterised by non-trivial spectral densities. In particular, we consider environments with a finite bandwidth and show that in the low temperature regime: i) secular terms in the master equation may be neglected; ii) attenuation (damping) is strongly suppressed; iii) the overall diffusion process may be described as a Gaussian noise channel with variance depending only on the bandwidth. We find several regimes where propagation is not much detrimental and entanglement may be protected form decoherence.

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Berihu Teklu, Matteo Bina, Matteo G. A. Paris. 2022-05-16. Noisy propagation of Gaussian states in optical media with finite bandwidth. https://doi.org/10.1038/s41598-022-15865-5

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